Warning device



Nov. 22, 1927. 1,650,419

R. s. BLAIR ET AL WARNING DEVICE Filed July 12, 1921 4 Sheets-Sheet lPatented Nov. 22, i927.

ROBERT S. BLAZE, 'OF SOUND BEACH, ANIIBURLING D. "WELLS; 0F IDA'NBURY,COlfi- NECTICUT; SAID WELLS ASSIGNSR- T0 SAID BLAIR.

wennlne env ron.

Application filed July 12,

This invention refers to warning signals and more p rticulnrly todevices of such nature as may be used for giving warning of the approachof railroad trains to grade crossings.

One of the objects thereof is to provide a signal of simpleconstruct-ion but durable and reliable in action, Another object is toprovide a. signal whichrequires no auxiliary energy for its operation.Another object is to provide asignal whirl n'ury be attached to one ofthe rails of i1. 'road truck and adapted to be operated by thevibrations of the rail due to the train 'unningupon that track thusannouncing the approach of a train on the track to which the signal isattzrch'ed while the train is yet at a considerable distance. Anotherobject is to provide a signal of such construction as to be proofagainst tempering and which cannot be re moved from the truck except bya person possessing the key to its lock or by conr p'letely demolishingit. Another object is to provide a signal which will not be inade inoperative by snow, rain O'Iflllud unless C0111- plete'ly buried thereby.Another object is to provide -a. method of utilizing the vibrations ofthe rails of a railroad es :1. source of energy to operate a signal.Otherobjects will be in part obvious and in part pointed out hereinafterThe invention accordingly consists in the features of construction.combinations of elements and arrangements of parts which will heexemplified in the structure hereinafter described and the scope of theapplication of which will be indicated in the ilt'ollowing claims.

1n the accompanying drmvings in which is shown one of the variouspossible embodiments of this invention. Figure l is a side elevation incross section of a. signal fastened on the lower side of e standardrailroad mil. the end of one of the ties which supports the rail is alsoshown. Figure 11 is a plan view in cross section of the showninFigfure 1. the section bein A .1. clone the line 1-1 in the directionus indicated by the arrows in Figure I. showing the mechanism forrelide'rinu the signal inoperative. Fig ure H? is :i oss sectionn} viewtaken along the i i re ll inthe direct on 1921. Serial No. 434,113.

of the controlling mechanism for rendering the signal inoperative.Figure IV is a plan view of the lever by means 0T which the signal "maybe made inoperative and the "spring whiehholds th'eleve'r in eithertheon erefl' position but prevents the lever from takingany position midwayof these two positions. Figure V is a niodificatioinehd is a plan viewof the head of the bolts which secure the signal to the truck. Figure VIis a side elevation in cross sectionof a signal fastened on the lowerside of a. standard railroad rail. Figure VII a pla n view in crosssection of lhe signal shown in Figure VI, the section being taken alongthe line 3+3 in the direction es indicated by the arrows.

Similar reference characters refer to sim't,

ler parts throughout in the various views or the druwings. i r

Turning now to Figure I we have one oi. the rails 10 of x a railroadtrack having clamped to the lower surface "of its bzrse flange anexterior casing 11 by means ofe plurality of bolts such as 12 which hookover the edge of the base flange of the rail 10 and their threaded endspassing through holes in the exterior casing 11 are secured by the nuts13 which securely hold the eX- terior casing 11 up against the baseflange. The bolts 12 are formed with square shoulders which bear againstthe edge of the 'base flange of the rail 10 and prevent thei'n frombeing swung a'rouud. out of engagement therewith thus making itimpossible to re move the exterior casing 11 endth'e mechanism containedtherein from the rail 1i0except by reinovingg the nuts Thelower end oftthe exterior casing 11 is formed with the flange bolted on to which is:1. horn 14 by means of screws suchus'15. A. lug 16 on the flange of thehorn 14 is so formed as v to engage with the flange ont-he lowerjend oilthe exterior casing 11 and diametrically 015- although the screws suchas 15 have be in ured; ii. screen 19 is rive? the by rivets such as :20re j} cm the sertion of sticks and stones therein to stop the action ofthe signal. A small hole is drilled in the lowest part of the horn 14 toact as a drain. A case 21 flanged at its lower end has clamped thereon athin metal diaphragm 22 by a ring 23 which is securely held thereon byscrews such as 24 tapped into the case 21. A gasket such as 25 is placedon each side of the metal diaphragm 22 making a water tight jointtherebetween and the case 21 and also protecting the metal diaphragm 22from minor deformations due to the inequalities of the surfaces betweenwhich it is clamped. At the corners of the case 21 which is square inform are secured two lugs such as 26 formed on the inside of theexterior casing 11 by means of screws such as 27. A metal bellows 28.circular 1H form and spun from very flexible metal has secured to itsupper end by sweating with solder or by some similar process a block 29which is in turn fastened to the center of the inside surface of the endof the case 21 by means of flat headed screws such as 30,

there being secured to the other end of the metal bellows 28 in a mannersimilar to which the block 29 was secured thereon a flange 31 which isfastened to the center of the inertia member 32 by screws such as 38which pass through a flange 34 which is fastened'to the end of the metalbellows 35 and which is similar in construction to the metal bellows 28butwhich is much smaller in diameter, the other end thereof havingfastened thereto a stud 36 which passes through ahole in the center ofthe metallic diahragm 22 and is securely gripped thereto y a pair oflock nuts suchas 37. A pair of askets such as 33 is interposed betweenthe aces of the flanges 34 and 31 and the inertia member 32 makingatight joint therewith. a hole passes through the center of the flange31, the inertia member 32 and the flange 34 affording a clear passagewaybetween the metal bellows 35 and 28. The relative diameter of the metalbellows 35 and 28 determines the ratio of the movement of the metaldiaphragm 22 which is fastened to the metal bellows 35 and the inertiamember 32 which is fastened to the adjacent ends of the metal bellows 28and 35; thus a relatively small movement of the inertia member 32 alongthe axis of the metal bellows 28 and 35 will result in a comparativelylarge movement of the metal bellows 35 and the metal diaphragm 22secured thereto because of the necessity of the metal bellows 35 havingto elongate to a considerable extent in order to change its volume tothe same extent as that change which took place in the volume of themetal bellows 28, as they are both entirely filled with a fluid nearlyincompressible and freezing at a very low temperature, for instancekerosene. A ring-shaped rubber bumper 39 is fastened to the inside ofthe case 21 by screws such as 40 and is so located that in case the rail10 to which the apparatus above described is fastened should receive adownward impulse of such degree as would threaten the safe operation ofthe signal above described the inertia member 32 would come into contactwith the ringshaped rubber bumper 39 thus preventing undue movement ofthe metal diaphragm 22 by reason of limiting the degree of deformationof the metal bellows 28. Turning now to Figure II we have a shaft 41journaled in a boss 42 on the inside of the case 21 and having pinnedonto the lower end thereof a bell crank 43 by means of a pin 44. Turningnow to Figure III we have a shaft journaled in a boss in the exteriorcasing 11 and has pinned on to its upper end by means of the pin 44 ahand lever 46, shaft 45 being flanged at its lower end and has driventherein a pa r of pins such as 47 which engage with two holes in asimilar flange on the end of the shaft 41, the shaft 41 and the shaftare so located in the case 21 and the eaterior casing 11 that their center lines coincide. A spring 48 has one end hooked around the stud 49 onlever 46, the other end thereof is hooked over a stud 50 in theexterior-casing 11. Returning now to Figure II we have a pair of linkssuch as 51 connected to the ends of the bell crank 43 by means of pinssuch as 52 their other end being secured to the ends of the latches 53by similar pins. Split pins such as 54 pass through the ends of the pins52 holding them securely in place in the ends of the links 51, thelatches 53 and the bell crank 43. The other ends of the latches 53 arewedgeshaped on their opposing edges and being swireled about a pair ofpins such as which are pressed into bosses such as 56 on the inside ofthe case 21 will engage with suitable grooves cut in the circun'ifcrenceof the inertia member 32 whenever the other ends of the latches 53 areswung out from each other by the rotation of the bell crank 4.3 in aproper direction. the motion of the hell crank 43 being carried to theends of the latches 53 by the links 51. A split pin 54 is passed throughthe lower ends of the pins preventing the latches 53 from droppingtherefrom. 'lurning now to Figure IV we have a stud 57 secured in theexterior casing 11 against which she. 57 the hand lever 46 is firmlyheld by the action of the spring 48 one end of which is hooked over thestud 49 in the hand lever 40 and its other end is hooked over the stud5(l'securcd in the exterior casing 11. The center line of the spring 48in the hand lever 46 as in the position shown in Figure IV lies to oneside of the center line of the shafts 4-1 and 45 thus holding the handlever 46 firmly against the stud 57. this position of the hand lever 46corresponds to the position of the bell crank Fill "nec osis i a;

s3 and of the latches 581and :the conne'oting upper end-loaf the case 21by means of screws linkages in the position as shown .'inFigure 11. thenthe hand lever 46 isnp against the stud 52' the signal is consequentlyunlocked and will operate whenever the rail 10 to which the :signalisattached should be caused to vi'orateby the approach of a railroad trainthereon. Turning now to Figure VL- said figure shows a form of thesignal abore described in which the vibrations of the rail to which itis attached are amplified i and transmitted @to a diaphragm ibymechanical means instead of by hydraulic means, as made use of in thelorm ofsi-gnal previously described. In Figure VI we have an exterio-rcasing [11 fastened to the lower side or the base flange of the rail 10by means of bolts such as 12 the heads of which hook over the edge oithe base flange of the rail 10 and their threaded ends pass throughholes in the upper end of the exterior casing 1.1 and have nuts such as-1'3 threaded thereon which upon being firmly screwed home securely holdthe exterior casing 11 against the bottom of the base flange of the rail10, a square shoulder on the shank of the bolts 12 just underthe'headsthereof enwith the edge or" the base flange 01 A the rail 10-aandprevents the removal of the exterior casing 11 therefrom by swinging theheads of the bolts l2 out from engagement with the :base flange of therail 10. The square should-er j ustnnder the head of the bolts 12 isclearly shown in Figure V. A case 21 having an opening in its right handside has vvclamped over thisiopening a metal diaphragm '58 by meansofthe clamping ring 59 which is held against the outside surface of themetal diaphragm '58 by a plurality of screws such as 60 which passtherethrough and are topped intothe case 21, gaskets such as 61 being placedon each side of the metal diaph 'agm 58 thus making certain themaintenance of annir tight joint between the metal diaphragm 58 and thewalls of the case 23.. An inertia member 62, seeFig. V1, is supportedwithin the case 21 upon a plurality of springs such as 63 which nest indepressions in the twb ends of the inertia member 62 and bear again-stthe adjaren-t'cnds oi' the case 21 thus supporting the inertia member 62at a distance from each of the ends ott the case '21. Four links such asor are swiveled at one end upon a pair of long'pins 65' which passthrough lugs such as .66 integral with the inside surface or the case21. The other tends of the links 614 engage with pins such as 67 whichpass through holes in the side of the inertia n1e1nher 62.v the function"of the links (it is to maintain parallelism between the center line.oi. the inertia member 62 and the center line of the case 21. Aring-shaped rubber bumper 68 in axial alignment with the inertia member62 is secured "to the inside surfaceof the such :as 69 tapped into the:case 21, their heads, being-countersunkdeeply within the rubber bumperso that whenever theinentia member 62 comes into contact therewith thescrews 69 will not impede the absorption of the force of the blow by therubber bumper (38. The springs such as 63 which arenested in depressionsin the upper endof the inertia' nember 62 pass through holes in therubber bumper 68 provided so that they may get a rfirlm bearing upon theend of the case 21. The lower end of the case 21 is closed by a cover 70secured to the lower end thereof by screws such as 71 which are tappedinto a flange on the bottom end oi the case 21, a gasket 72 isinterposed between the cover 70 and the case 21 to insure 1awvater tightjoint therebetween. The case 21 and the mechanism assembled there inheld within the exterior casing 11 by means of screws such as 71, thealternate screws which secure the cover 70 to the case 21 are not tappedinto the case 21-but pass through the cover 70 and the flange on thebottom of the case 21 finally screwing into a lug on the inside of theexterior casing 11 thus securely holding the case :21 to the exteriorcasing- 11. By removing the alternate screws such as 71 which aretl-n'eadedinto the lug 72 the case :21 and the n'lec lmnism containedtherein may be renroved as a unit from the exterior casing 11. :lhreadedinto the oenterof the lower end of the inertia member -62 is abushing 73which may be locked to the inertia member 62 by means oit a check nut74., a toggle anchor 75 the lower end of which is circular in formpasses through the bushing 7 and has threaded on. its lower end a checknut 76 which permits a locking ot the toggle anchor 75 to the bushing 78by screwing the check' nut 76 tightly :up against the lower end or thebushing 73, the lower end of the toggle anchor 75 is made square in formso that "a wrench may be used to hold it from turning whenever the checknut 76 threaded thereon is loosened or tightened up. The upper end ofthe toggle anchor'75whic h is considerably,

larger than the round portion which passes 1 through the bushing (3 andforms a shoulder which bears against the upper end thereof 1s slottedand provided with a clamping screw lug 7 9 on the inside of the upperend oi the case 21 in a similar manner by a clamping screw 7?, two pairsof blocks such as 80 are riveted :to the toggle 78 by rlvets such as 8 6so that whenever 'flexion takes place therein all thebending will belocalized at three points, that is: immediately adjacent to the pointsof attachment of the toggle 78 to the toggle anchor and the lug 79 andalso at the center of the length of the toggle 78 between the two pairsof blocks 80 where the shaft 81 which connects the metal diaphragm 58thereto by means of two pairs of check nuts such as 82 threaded on thetwo ends of the shaft 81. and securely fasten the respective'endsthereof to the metal diaphragm 58, and the toggle 78. T he cover 70 isprovided with a hole at its center in co-axial alignment with the centerof the bushing 7 3 and is closed by means of a cap such as 83 which isfastened thereon by means of screws such as 60, a gasket 87 isinterposed between the flange on the end of the cap 83 and the cover 70to insure the maintenance of an air tight joint therebetween. On theright hand side of the exterior casing 11 there is secured a horn 14 bymeans of screws such as 60, the mouth of which is closed by means of ascreen 19 which is flanged over at its edge and riveted to the horn 14by means of rivets such as 20. This screen permits easy egress of allsound which is generated by the vibration of the metal diaphragm 58which is directly in line therewith but at the same time prevents theintroduction of sticks and stones to block the movement of the metaldiaphragm 58. A small hole 84 is drilled in the lower part of the horn14 to permit any moisture which may enter the horn 14 to drain therefromwithout entering the interior of the exterior casing 11. The lower endof the exterior casing 11 is closed by a plate 85 secured thereto bymeans of screws such as 15. The removal of the plate 85 by anyone otherthan those who have authority to do so is prevented by passing the barof a padlock 18 through a hole in the edge of the plate 85 and through ahole in the flange on the lower end of the exterior casing 11 whichregisters therewith, and a lug 86 on the upper side of the plate 85which hooks over the inside edge of the flange on the lower end of theexterior casing 11 makes it-impossible to remove the plate 85 even ifall the screws 15 have been removed therefrom until the padlock 18 hasbeen unlocked by using a proper key. Turning now to Figure VII we hai ca pair of latches 53 swiveled upon a pair of pins 55 which are mountedin bosses such as 56 whiclrare integral with the inside surface of thecase 21, theends of these latches 53 are wedge-shaped In section alongthe edges adjacent to the inertia member 62 and upon the propermanipulation of the handle46 shown in Figure II engage with suitablegrooves cut in the side of the inertia member 62 and prevent movementthereof relative to the case 21. The linkage connecting the handle 46with the latches 53 is identical in design both in the ease of thehydraulic and mechanical forms of the signal above described and isconsequently shown and described only with reference to the hydraulicform of the signal which was described above.

The operation of the hydraulic form of the apparatus above described issubstantially as' follows: The signal is bolted to the bottom of thebase flange of the rail 10 as shown in Figure I, between two of the tieswhich support the railroad track of which the rail shown at 10 in FigureI is a part. In order to gain access to the nuts 13 on the ends of thebolts 12 it is necessary to remove the case 21 and the mechanismcontained therein from the exterior casing 11 which is accomplished byremoving the screws 15 which secure the born 14 to the lower end of theexterior casing 11 and upon unlocking the padlock 18 it is possible byswinging the left hand end of the flange of the horn 14 downwardly tothe right and finally disengaging the lug 1(5 'i'rom engagement with theflange on the lower part of the exterior casing 11 to completely removethe horn 14. The case 21 is now removed by unscrewing the screws 27which pass entirely through the ring 23, the gaskets and the flange onthe lower end of the case 21 and secure the flange to the lug 26 on theinside surface of the exterior casing 11. The screws such as 24 whichfasten the ring 23 and the metal diaphragm 22 vand its gaskets 25 to thecase 21 are not disturbed thus the working mechanism proper of thesignal is removed from the exterior casing 11 without destroying any ofits adjustments. The exterior casing 11 is now held up against thebottom of the base flange of the rail 10 and the bolts 12 are insertedthrough the holes in the top of the exterior casing 11 with their headslapping over the edge of the base flange of the rail 10 and the nuts 13are firmly screwed up by inserting a wrench into the casing 11, thesquare shoulder just under the head of the bolt 12 as shown in Figure Vabuts against the edge of the base flange of the rail 10 and preventsthe bolts 12 from turning as the nuts 13 are screwed up. The exteriorcasing 11 having been securely fastened to the rail 10 the signal isreassembled by a procedure similar to that by which it was taken apartpreparatory to its attachment to the rail 10 as above described. heninserting the case 21 into the exterior casing 11 it is essential thatthe holes in the flange on the upper end of the shaft 41 should engagewith the pins in the flange on the lower end of the shaft 45 as shown inFigure III otherwise it will be impossible for an employee of therailroad to render the signal inoperative at such times when there is noneed of a warning signal in the locality where the signal has beenapplied to the railroad track. As is well known, an approaching trainsets up very rapid vibrations oi the rails so that the approach of atrain to a place where the highway cro s a railroad track can be readilydetermine-Q by l tening to the hum of the 1a 1; which is {p u 1 audibleeven when the train is beyond the ange of vision. This signal has beendesigned to be operated by the vet ill component of the vibration of theIt. be baseof which it has been attached, altiliough certain of thebroader features of the invention are not limited to such use. Theentire mechanism of the signal above described contained in the exteriorcasing 11 is rigidly connected with the rail 10 with the execution ofthe inertia member 32' i l i which is flexibly supported by the metalbelllows 28 and consequently as the rail 10 vibrates in that directionalong the center line drawn through the twoametal bellows 35 and 28 theinertia member 32 will tend to remain at rest wliile the remainder oithe mechanism of the signal will follow the vibration of the rail it);The inertia member 32 at best will not entirely remain at rest but willvibrate with an amplitude which will be considerably less than that ofthe rail 10. Let us consider the rail 10 moving downward through oneofits cycles of vibration, the inertia member 32 not being rigidlyconnected with the rail 10" will move downward to a lesser degree andeven under certain conditions of vibration its downward movement duringthe downward movement of the rail lOwill' hardly be discernible and willcause a considerable shortening of the metal bellows 2S and acorresponding decrease in the V01 ume thereof. The slight downward move?ment of the inertia member 82 and the appreciabledownward movement ofthe case 21 may be considered as an appreciable:

moveinent towards eachotherand although the upper end 01' the metalbellows 35 which is connected to the inertia member 32 by means or theflange an and the screws 83 moves downward therewith, the increase inthe volume contained in the metal bellows 3 5 is very small comparedwith the decrease in volume in the metal bellows 28 and as the 7 metalbellows 35and the metal bellows 28 are connected to each other by thepassagewayover the flanges 34 and 31 connected there with a portion ofthe fluid contained in the metal bellows 28 will be driven down throughthe passageway into the metal bellows 35 and result in a considerableextension thereof driving the metal diaphragm 22 downward by reason ofthe lower end of the metal bellows 35 being connected therewith by thestud 36 and the two look nuts 37. When the rail 10 reachesthe lowestpoint of its downward movement during the cycle of its vibration underthe action of an ap preaching train and starts on. the return movementthe inertia member 32 will lag behind the rest of the mechanismcontained in the exterior casing 11 and as there is thus set up arelative movement of the inertia member 32 away from the upper enduotthe case 21 an appreciable lengthening of the metal bellows 28 and acorresponding increase of its internal volume will takeplace by reasonof its upper end bein secured to the case 21 which is moving upward awaytrom the inertia member: 32 to ,whldh the lower endof the metal bellows.28 is task, toned by means of the flange 31 and: the screws 38. Theresultant increase in volume of the metal bellows 28 will cause a slightdrop in pressure therein resulting in the-flow 1 a of the fluidcontained in the metal bellows 35 through the passageway connecting; it.with the fluid contained. therein by the upper metal bellows 28 due tothe fact that the. up per metal bellows 28 has a very large diameter incomparison with the diameter of the lower metal bellows 35. 'The lowermetal? bellows 35 having been caused to shorten its axial length quiteappreciably as above described and its upper e'ndbeing secured to theinertia member 32 by means of the-flange 3st and the screws 33cwhichpass threethrough and screw intoithe flange 31 thus holding the upperend thereof in a compare tive state ofrest with the case 21,, a markedupward movement of the center of. the metal diaphragm 22, will resulttromthe stud 36 which is integral with the lower ends of the metalbellows 35 moving upwardly therewith lift'ing the center of the metaldiaphragm 22 by reason of its being secured to the center of the metaldiaphragm 22 by the two lock'nuts 37. From the above deserip ion of theoperation of the signal it will be seen that the vibration ofthe rail 10will be. greatly amplified and transmitted to the: metal diaphragm 2221sthe inertia. member 32, in holding the adjacent ends of the metalbellows 35 and 28 approximately stationary causing the fluid containedtherein toflow from one to the otheria violent sound will be generatedby the metal diaphragm 22 acting upon the air in the horn 14c and thenoise thus generated will pass out through the screen 19 which coversthe end of the born 14:. i

The operation of the mechanical formv of the signal above: described andshown Figures VI and VII of'tlie drawings is su stantially as follows: Atrain approaching upon the track to the base of one of the rails 10 ofwhich is attached the signal shown in Figures VI and VII, will causevibration of the rail 10th a degree depending upon the proximity'of thetrain to the point on the track wherethe signal is attached. Thevertical component of the vibration of the rail 10 will cause an up anddown movement of the exterior casing 11 which is securely fastenedthereto, by the bolts 12 and'all the mechanism of the signal which maybe rigidly connected to the exterior casing 11 will vibrate in harmonywith the rail 10. The rail 10 vibrates in other directions than inthevertical plane but it is the vibrations which lie in this plane onlythat we are interested in as the signal above described is designed tomake use of these vibrations onl As the exterior casing 11 moves up andown with the rail 10 the inertia member 62 which is not rigidlyconnected in any way therewith tends to lag behind and also in additionto its lag the amplitude of vibration thereof will be considerably lessthan the amplitude of vibration of the exterior casing 11 and the rail10 to which it is attached.

From theabove description of the action of the inertia member 62' itwill be seen that the lower end of the toggle 78 which is rigidlyconnected to the inertia member 62 by means of the toggle anchor 75which is in turn clamped in the bushing 73 by the lock nut 76, is heldsubstantially in a state of rest while the upper end thereof which isclamped in the lugs 79 by the clamping screw 77 is subjected to allmovements which the case 21'acquires through its rigid connectionwith'the exterior casing 11 and the rail. lO'to which it is rigidlyconnected. As the distance between the two ends of the toggle 78increases and diminishes due to the up and downward movement of the case21 while the inertia member 62 remains substantially at rest it willcause a lateral movement of the toggle 78 which will be much greater inextent than the movement of the rail 10 and the parts of the signalconnected thereto due to the well known action of the ordinary togglelinkage construction which is embodied in this apparatus in the form ofthe toggle 7 8 constructed of a thin strip of resilient material. Thedegree of lateral movement of the center of the toggle 78 and the shaft81 and the metal diaphragm 58 which is connected to its right hand endby means of the check nuts 82 may be varied at will by moving the lowerend of the reg gle 78 where it is connected to the toggle anchor 7 5 upor down by loosening the check nuts 7 6 and 60 and then adjusting theposition of the toggle anchor 75 by raising or lowering the bushing 7 3and the desired adjustment having been obtained the adjusting means issecurely locked again by screwing up the check nuts 76 and 60. Todiminish the degree of amplification of the vi brations of the rail 10during their transmission to the metal diaphragm 58 it is only necessaryto ra se the bushing 73 as above described thus forming a more acuteangle at the center of the toggle 78 thus a downward movement of theupper end of the toggle 78 while the lower end is held stationary willcause a smaller lateral movement of the shaft 81 than would be the caseif the bushing 73 had been moved downward increasing the angle formed atthe center of the toggle 78. As is well known, when the two links of thetoggle very nearly fall in the same straight line a very large movementof the connecting ends of the respective links in a directionperpendicular to a line passing through their other two ends will resultin a very small movement along that line and in the case where the twolinks of the toggle 78 form a rather acute angle with each other alateral movement of the connecting ends of the two toggle links willcause a much smaller movement of the other ends of the two toggle linksin the direction of a line passing therethrou h. Thus it will be seenthat there is 1)10Vl( ed means adapted to permit the adjustment of thesound which the signal above described has been designed to produce,permitting it to be used on rails of various degrees of rigidity andover which different weights of railroad equipment pass. The signal maybe adjusted by removing the plate 85 and the cap 83 as above describedif it is desired to regulate the tone of the signal after it has beenattached to the base of the rail 10. If the signal were subjected tovery great vibrations which would endanger the proper operation of theapparatus the inertia member 62 will come into contact with the rubberbumper 68 thus limiting its upward movement relative to the case 21 andpreventing the metal diaphragm 58 from being ruptured, movement in adownward position relative to the case 21 could be retarded by thetoggle 78 straightening out.

The intensity of the sound generated by the signal above described willrapidly increase as the train approaches the grade crossing or a pointwhere the signal is attached to the track thus making, it possible forone to readily tell whether the train is approaching or receding fromthat point by listening for a few moments to the warning signal.

From the above it will be seen that there provided an art and anapparatus wherein the desired results are obtained.

As various possible eml'iodiments might be made in the illustrativeapparatus above described and as various changes might be made in theart herein set forth it is to be 'nceonis understood that all matterherein set forth or shown in the accompanying drawings is to beinterpreted as illustrative. and not in a limiting sense.

We claim: 7 1 y l. iheherein described art which consists in utiiizingthe vibration of a railway rail to vibrate one of two members relativeto another, l-imitii'ig said vibratory movement, moving said members useunit with the rail as it is depressed by the passage of a car wheel i ito cause rhe operultionof an alarm signal.

2. The herein described urtwhich consists in utilizing the vibration ofarailway rail, amplifying the extent of such vibration in anotherinemberand utilizing the sound vibration of the second member as an alarm.

- 3. The herein described art which consists in utilizing thevibrationcoi a railway rail to cause the vibration of another member,utilizing the sound caused by the latter vibration as an alarm andlimiting: the effect of depression of the rail ,upon the second memberasarica r wheel, passes over the point at which the vibration of the railis utilized.

l. In construction for alarm signals, in combination, a railway rail, avibratory sound-producing member adapted to serve as an alarm, onactuating member mounted to be vibrated by said rail and to be movedtherewith upon said rai'l being depressed by the passage of a car wheelthereover, and transmitting means interposed between said actuatingmember and said vibratory member adapted to cause the vibration ofthelatter with a greater amplitude than that of the vibration of saidrail by the energy of vibration of the rail.

5. In construction for alarm signals, in combination, a railway rail, avibratory sound-producing member adapted to serve as an alarm signal,and transm1tt1ng means interposed between said rail and saidv membercomposed of a series of connected physical bodies adapted to vibratesaid member with an increased amplitude from the vibration of said rail.y

6. In construction for alarm signals, in

combination, a railway rail, a vibratory sound-producng member connectedtherewith to be operated thereby and. means adapted to prevent excesseffect upon said vibratory member, upon the rail-being depressedby thepassage of a car wheel thereover.

7. in construction for alarm signals, in combination, a vibratorymember, a vibratory sound-producing member; a. third mem her and meansconnected with said third member to transmit vibrations of said firstmember to said sound-producing member and scorer, and utilizing saidvibration sound-producing me'mberha third member movablewith respect tosaid rail and said sound-producing' mei'nber and means connecting railand said sound-producing member to vibrate the latter fi'lOIIl thevibrationswot said rail and utilizing the inertia of first member moves,and an alarm signal;

adapted to be actuated ,on the vibration of said first member by saidrail.- 10. In construction foralarm signals, vin combination, a railwayrail, a device secured to said rail and comprising amembericonnect'cd L0be vibrated by the vibration of said rail, means on said device adaptedto limit the amplitude of said vibration, where byisaid device isdepressed with said 'rail upon the depression of ithe rail by thepassage of a car wheel thereover without excessive movement ofsaidvibrated member, and an alarm signal connected with said device to beactuated upon saidmember being vibrated by said rail.

11. In construction for alarm signals, in combination, a railway rail,adevice secured to said rail and comprising a member con nected to bevibrated by the vibration of said rail whereby said device is depresseded to vibrate said alarm signals with an increased amplitude withrespect to that of said rail upon said first member being vibrated bysaid rail. y

12. In construction for alarm signals, in combination, a railway rail, asubstantially enclosed casing secured to said rail and adapted to bedepressed therewith upon the passage of a car wheel thereover, an alarmdevice, and means within said casing adapted to utilize the vibration ofsaid rail to actuate said alarm.

13. In construction for alarm signals, in combination, a railway railand an alarm device adapted to be actuated by the vibration of saidrail, said alarm device being connected to said rail.

mounted in a substantially enclosed casing 14; In construction for alarmsignals, in

combination, a rail, an alarm device, a connecting member, positivelyacting means adapted upon said rail vibrating to move said connectingmember positively throughout adistance greater than the amplitude ofvibration of the rail, and means adapted to utilize such movement tocause the actuation of said alarm device.

15. In Construction for alarm signals, in combination, a railway rail,an alarm device, means connected to said rail adapted by the vibrationof the latter to cause said alarm device to vibrate throughout adistance greater than the amplitude of vibration of said rail.

16. In construction for alarm signals, in combination, arailway rail, acasing connected thereto, an inner casing mounted within said firstcasing and having a vibratory member associated therewith, an alarmdevice, and means associated with said inner casing adapted to utilizethe vibration of said rail to actuate said alarm. I

17. In signalling apparatus, a .device vfor causing an alarm signal tobe operated comprising a casing secured to a rail to move therewith andcontaining a plurality of members one of which is relatively heavy andadapted to act by its inertia and thereby serve as a point ofsubstantially fixed support for a portion of another of said members,which latter member is adapted 26 to be vibrated by said rail withrespect to said first member and by its vibration to cause the alarm tobe actuated.

18. In construction for alarm signals, in combination, a railway rail,an alarm device adapted to be actuated by the vibration of said rail, acasing about said alarm device and secured to said rail and having anopen ing therein adapted to permit exit therefrom of sound waves fromsaid alarm device, and screening means associated with said opening.

19. In construction for alarm signals in combination, a railway rail, analarm device adapted to be actuated by the vibration of said rail, acasing about said alarm device 40 and secured to said rail and having anopenmg therein adapted to permit exit there from of sound waves fromsaid alarm device, and means associated with said casing

